Figure 7. B7.2 controls VACV-specific CD8 T cell responses independent of CD4 T cells.
(a) Wt or (b) MHC-Class II deficient (Class-II−/−) mice were infected i.p with VACV-WR (2 × 105 PFU/mouse). (a) As indicated, groups of WT mice were depleted of CD4 (αCD4) T cells prior to VACV infection. Wild-type (a and b), CD4-depleted (a) or Class-II−/− (b) mice were injected i.p on days 0, 1, 2, and 3, with 150 µg of either control IgG or anti-B7.2 in PBS. Seven days post-infection splenocytes were harvested and stained for CD3, CD4, CD8 (a; top panel) or CD8, CD44, B8R-tetramer (a; bottom panel and b). (a) Top: Representative plots of CD4 and CD8 staining, gating on CD3 cells. Percentages of CD3+CD4+ and CD3+CD8+ T cells are indicated. Bottom: Representative plots of tetramer staining, gating on CD8 cells. Percentages of activated B8R-tetramer positive CD8 T cells (CD8+CD44+B8R+) are indicated. Total numbers of B8R-tetramer positive CD8+CD44+ T cells per spleen are shown. Results are mean number ± SEM (n=4 mice/group) from one experiment. *, p < 0.05 (wt mice vs knockout or anti-B7.2 treated) as determined by Student’s t test. Similar results were obtained in 2 separate experiments.